/*
 *
 * (c) Copyright Ascensio System Limited 2010-2018
 *
 * This program is freeware. You can redistribute it and/or modify it under the terms of the GNU 
 * General Public License (GPL) version 3 as published by the Free Software Foundation (https://www.gnu.org/copyleft/gpl.html). 
 * In accordance with Section 7(a) of the GNU GPL its Section 15 shall be amended to the effect that 
 * Ascensio System SIA expressly excludes the warranty of non-infringement of any third-party rights.
 *
 * THIS PROGRAM IS DISTRIBUTED WITHOUT ANY WARRANTY; WITHOUT EVEN THE IMPLIED WARRANTY OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. For more details, see GNU GPL at https://www.gnu.org/copyleft/gpl.html
 *
 * You can contact Ascensio System SIA by email at sales@onlyoffice.com
 *
 * The interactive user interfaces in modified source and object code versions of ONLYOFFICE must display 
 * Appropriate Legal Notices, as required under Section 5 of the GNU GPL version 3.
 *
 * Pursuant to Section 7 § 3(b) of the GNU GPL you must retain the original ONLYOFFICE logo which contains 
 * relevant author attributions when distributing the software. If the display of the logo in its graphic 
 * form is not reasonably feasible for technical reasons, you must include the words "Powered by ONLYOFFICE" 
 * in every copy of the program you distribute. 
 * Pursuant to Section 7 § 3(e) we decline to grant you any rights under trademark law for use of our trademarks.
 *
*/


namespace ASC.Mail.Net.SMTP
{
    /// <summary>
    /// This value implements SMTP Notify value. Defined in RFC 1891.
    /// </summary>
    public enum SMTP_Notify
    {
        /// <summary>
        /// Notify value not specified.
        /// </summary>
        /// <remarks>
        /// For compatibility with SMTP clients that do not use the NOTIFY
        /// facility, the absence of a NOTIFY parameter in a RCPT command may be
        /// interpreted as either NOTIFY=FAILURE or NOTIFY=FAILURE,DELAY.
        /// </remarks>
        NotSpecified = 0,

        /// <summary>
        /// DSN should not be returned to the sender under any conditions.
        /// </summary>
        Never = 0xFF,

        /// <summary>
        /// DSN should be sent on successful delivery.
        /// </summary>
        Success = 2,

        /// <summary>
        /// DSN should be sent on delivery failure.
        /// </summary>
        Failure = 4,

        /// <summary>
        /// This value indicates the sender's willingness to receive "delayed" DSNs.
        /// </summary>
        Delay = 8,
    }
}